[R.B.]

For the avoidance of doubt there is a mass of evidence that fluoride has an important role in the hardness of enamel, and topical delivery (viz toothpaste) has been shown to increase hardness of enamel, but it appears there may be non-flouridated products that also increase enamel hardness.

Fluoride is found in sea water and soil, and certainly has a role in the biological function of the body. As with many things the level of toxicity is in the dose; many things that are essential to human existence are toxic in abnormal amounts including water. It does appear that the level of flouride intake in breast fed infants is low, and nature evolution or intelligent design appears to have arranged it that way, so maybe there is a lesson there.

However overall fouride is not per se toxic, but is harmful in inappropriate amounts in the given circumstances, which will depend on other dietary factors, age, and probably genetic makeup . . .

http://www.google.com/url?sa=t&rct=j...56643336,d.ZGU This paper looked at 5 different tooth pastes some with fluoride and some without on extracted teeth in artificial saliva. Interestingly the non fluoridated products had similar effects on hardness.

It is also interesting that they used chlorinated water to soften the teeth first. OK it was for 24 hours, but the fact is still thought provoking given "There have been several case reports of competitive swimmers suffering dental erosion from swimming in gas-chlorinated pools (Centerwall et al, 1986)."

Toothpaste can contain large amounts of fluoride. In this paper those pastes that contained fluoride had 900 - 1000 mg of fluoride per kg. For this reason it is important not to swallow or eat toothpaste, and to rinse really well after brushing. Further apparently the amount used should be the size of a pea rather than a wide strip down the brush.

As a child I and others would occasionally eat small amounts of toothpaste because it tasted good, used the lots on the brush because that is what they did in the adverts, and were not very fussy about rinsing because we knew that toothpaste was good for teeth. Nobody mentioned the wider issues of fluoride excess.

The debate is are there better ways of delivering products fluoride to teeth that may protect them against erosion than inclusion in drinking water, and are any potential benefits of fluoridation of water outweighed by other heath risks brought by the additive effect of fluoride in water, in addition to the modern-day increased occurrence of fluoride in the environment and in foods?